Gymnasium floors are frequently synthetic plastic surfaces and may be surfaced with one or more polyurethane coatings which abrade in use. In due course these old and abraded surface coatings must be resurfaced. From the standpoint of cost and minimization of solvent fumes, it is desired to achieve the desired resurfacing with water-based organic coatings. While various types of organic coatings are available in aqueous medium and would be useful for the intended purpose, these adhere poorly to the old and abraded polyurethane surface coating which must be overcoated, so these water-based organic coatings cannot be effectively used. It is the objective of this invention to enable the use of such aqueous coatings for the described purpose. It is another objective of this invention to enable the use of aqueous coatings on unabraded synthetic surfaces to provide protection against abrasion for extended periods and to provide for ease of resurfacing, when necessary.